1. Field of the Invention
The present invention relates to an oxygen concentration regulator using an oxygen ion conductive solid electrolyte.
2. Description of the Prior Art
As the oxygen concentration regulator of this type, there has hitherto been known an oxygen concentration regulator using, for example, a zirconia ceramics as the oxygen ion conductive solid electrolyte (hereinafter referred to as solid electrolyte), wherein the zirconia ceramics is used as a partition wall, a pair of electrodes such as platinum or the like are arranged on both sides of the partition wall, and a direct current voltage is applied across both the electrodes, whereby oxygen is moved from one of the electrodes to the other to control an oxygen concentration on one electrode side.
However, the solid electrolyte is small in electric conductivity at room temperature and becomes impractical, while higher temperature is required to reduce the polarization of the electrode such as platinum or the like, so that the above mentioned regulators are usually used in an electric furnace maintained at a high temperature. Therefore, the conventional oxygen concentration regulators with a system of flowing a direct current through the solid electrolyte have drawbacks that a large power is required for the heating of the electric furnace, and the structure of the regulator as a whole is complicated and becomes large-sized.